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感谢这个精彩的教程，我创建了一个 3D 地图的 gif 图像，以便可视化惠灵顿市中心 12 米海平面上升的蔓延！

地图截图：

现在我想知道是否可以在使用“render_movie”功能创建的视频中保留标签、比例尺和指南针？我一直在寻找很多教程，但到目前为止还没有成功！有人可以帮我解决这个问题吗？

#GENERATE MP4:

n_frames <- 1080 
waterdepths <- transition_values(from = 0, to = 12.3, steps = n_frames) 

# video transition variables

theta <- transition_values(from = -45, to = 180, steps = n_frames, one_way = TRUE, type = "lin")
phi <- transition_values(from = 40, to = 10, steps = n_frames, one_way = TRUE, type = "cos")
zoom <- transition_values(from = 0.8, to = 0.3, steps = n_frames, one_way = TRUE, type = "cos")

library(av)

zscale <- 2
elev_matrix %>% 
  sphere_shade(sunangle = 270, texture = "imhof1", zscale = zscale) %>%
  add_water(detect_water(elev_matrix), color = "imhof4") %>%
  add_shadow(ambient_shade(elev_matrix, zscale = zscale), 0.5) %>%
  add_shadow(ray_shade(elev_matrix, zscale = zscale, lambert = TRUE), 0.5) %>%
  add_overlay(overlay_img, alphalayer = 0.8) %>%
  plot_3d(elev_matrix, solid = TRUE, shadow = TRUE, zscale = zscale, 
          water = TRUE, watercolor = "imhof3", wateralpha = 0.8, 
          waterlinecolor = "#ffffff", waterlinealpha = 0.5,
          waterdepth = waterdepths/zscale, windowsize = c(1500, 1250))

render_label(elev_matrix, x = 700, y = 650, z = 1500, 
             zscale = 4, text = "Wellington", linecolor="black", freetype=FALSE)

render_label(elev_matrix, x = 1405, y = 1190, z = 800, 
             zscale = 4, text = "Mount Victoria", textcolor = "black", linecolor="darkred",dashed = TRUE, freetype=FALSE)

render_scalebar(limits=c(0, 5, 10),label_unit = "km",position = "W", y=50,
                scale_length = c(0.33,1))

render_compass(position = "E")


render_movie(
  filename = "wellington.mp4", type = "custom",
  frames = 1080,
  phi = phi,
  theta = theta,
  zoom = zoom
)

不幸的是，我只能通过代码的最后一部分在惠灵顿周围获得一个不错的场景（但没有标签，也没有海平面上升......）:(

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1 回答 1

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问题已解决（确保 ffmpeg 路径设置良好）：

代码：


#generate mp4
n_frames <- 1080 
waterdepths <- transition_values(from = 0.5, to = 12.3, steps = n_frames) 

#video transition variables
theta <- transition_values(from = -15, to = 180, steps = n_frames, one_way = FALSE, type = "lin") 
phi <- transition_values(from = 40, to = 15, steps = n_frames, one_way = FALSE, type = "cos")
zoom <- transition_values(from = 0.8, to = 0.3, steps = n_frames, one_way = FALSE, type = "cos") 


library(av)
zscale <- 2
elev_matrix %>% 
  sphere_shade(sunangle = 270, texture = "imhof1", zscale = zscale) %>%
  add_shadow(ambient_shade(elev_matrix, zscale = zscale), 0.5) %>%
  add_shadow(ray_shade(elev_matrix, zscale = zscale, lambert = TRUE), 0.5) %>%
  add_overlay(overlay_img, alphalayer = 0.8) %>%
  plot_3d(elev_matrix, solid = TRUE, shadow = TRUE, zscale = zscale, 
  windowsize = c(1200, 1000))   


render_label(elev_matrix, x = 700, y = 650, z = 1500, 
             zscale = 2, text = "Wellington", linecolor="black", freetype=FALSE)

render_label(elev_matrix, x = 1405, y = 1190, z = 800, 
             zscale = 2, text = "Mount Victoria", textcolor = "black", linecolor="darkred",dashed = TRUE, freetype=FALSE)



for(i in 1:1080) {

render_water(elev_matrix, watercolor = "lightblue", wateralpha = 0.8, 
               waterlinecolor = "#ffffff", waterlinealpha = 0.5,
               waterdepth = waterdepths[i]/zscale)

render_camera(theta=theta[i], phi=phi[i], zoom=zoom[i])

render_snapshot(filename = sprintf("welli%i.png", i), 
                title_text = "Wellington, New Zealand | Imagery: ESRI_Imagery | DSM: 1m, source: Open Topography",
                title_bar_color = "#1f5214", title_color = "white", title_bar_alpha = 1)
}
rgl::rgl.close()


av::av_encode_video(sprintf("welli%d.png",seq(1,1080,by=1)), framerate = 30,
                   output = "wellington.mp4")
于 2020-05-19T22:21:20.220 回答